Regex to match MAC address and also extract it's values

Question

I'm trying to first check if a string confirms the format of a MAC address, and if it does I would like to extract all the byte values out of the string.

So far I wrote this, and it successfully matches if the format of a mac address is correct or not:

 mac_regx = re.compile(r'^([0-9A-F]{1,2})(\:[0-9A-F]{1,2}){5}$', re.IGNORECASE)

But when I use this regex to extract the byte values, I'm only getting the first and the last one:

(Pdb) print(mac_regx.findall('aa:bb:cc:dd:ee:ff'))
[('aa', ':ff')]

I know I could simply split by : and that would do the job. I was just hoping to be able to do both, the matching and value extraction, in only one step with one regex.

Answer 1

If you want all the matches, you should avoid using {5}:

mac_regx = re.compile(r'^([0-9A-F]{1,2})\:([0-9A-F]{1,2})\:([0-9A-F]{1,2})\:([0-9A-F]{1,2})\:([0-9A-F]{1,2})\:([0-9A-F]{1,2})$', re.IGNORECASE)

or, shorter,

mac_regx = re.compile(r'^([0-9A-F]{1,2})' + '\:([0-9A-F]{1,2})'*5 + '$', re.IGNORECASE)

You could also make a list of 6 occurrences of a string '[0-9A-F]{1,2})' and join them with '\:'.